If moisture is allowed to reach the connection between the aforementioned components, which is usually produced by welding, a rapid corrosion of the aluminum must be feared which has a negative effect on the cable strength and thus the operational safety of the complete onboard power supply.
To be sure, attempts have previously been made to seal the connecting location between the components against moisture by using shrink-wrap hose and/or by using shrink-wrap hose/butyl strip seals and/or through insert-molding with polymers. These known sealing systems, however, cannot be used in practical operations for the temperature range of approximately −40° C. to approximately +230° C. and will therefore fail. Furthermore detrimental for a good sealing effect are the widely varying expansion coefficients of the materials used.
A method for covering micro-electric hybrid semiconductor circuits or micro-electronic semiconductor components is known from the DE 34 42 131 A1. With said method, the components located on a substrate are covered by pouring a soft, sealing layer of plastic over them, covering this layer with a compound foil of plastic and metal, and subsequently encapsulating it with synthetic resin. With this relatively involved method, a low-viscous, liquid elastomer is applied, for example, to form the soft sealing layer of synthetic material. A composite foil of plastic and metal is then placed onto this layer and is pressed against it with a hollow punch. A synthetic resin, especially a highly filled epoxy casting resin, is then used for the insert-molding or encapsulation.
A method for covering electric and electronic components or assemblies is known from the EP 0 361 194 A2, for which an intermediate layer of an elastic synthetic material is initially applied to the mechanically sensitive regions, which are then covered with an outer cover layer of a mechanically and chemically stable synthetic material. In the process, the outer covering layer as well as the intermediate layer are produced through injection-molding with molding compound in an injection molding tool. During the injection molding process, however, components to be encapsulated are subjected to relatively high pressure and temperature stresses.
The DE 10 2004 062 457 A1 discloses a water-absorbing composition with suppressed corrosiveness when in the swollen state, relative to copper, wherein its use is known for cable sheaths and for a sheathed cables.